Caligula is 2006 German-language opera by Detlev Glanert in four acts to a libretto by Hans-Ulrich Treichel, freely adapted from the 1945 play by Albert Camus. The published version by Boosey & Hawkes also includes an English version by Amanda Holden. The opera premiered at the Oper Frankfurt, conducted by Markus Stenz, directed by . The plot of Camus' play tells of the last days of Caligula.